/* * (C) 2016 by Sysmocom s.f.m.c. GmbH * All Rights Reserved * * Author: Philipp Maier * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU Affero General Public License as published by * the Free Software Foundation; either version 3 of the License, or * (at your option) any later version. * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU Affero General Public License for more details. * * You should have received a copy of the GNU Affero General Public License * along with this program. If not, see . * */ #include "config.h" #include #include #include #include #include #include #define IP_V4_ADDR_LEN 4 #define IP_V6_ADDR_LEN 16 #define IP_PORT_LEN 2 #define CHANNEL_TYPE_ELEMENT_MAXLEN 11 #define CHANNEL_TYPE_ELEMENT_MINLEN 3 #define ENCRYPT_INFO_ELEMENT_MINLEN 1 #ifdef HAVE_SYS_SOCKET_H #include #include /*! \addtogroup gsm0808 * @{ * \file gsm0808_utils.c */ /*! Encode TS 08.08 AoIP transport address IE * \param[out] msg Message Buffer to which to append IE * \param[in] ss Socket Address to be used in IE * \returns number of bytes added to \a msg */ uint8_t gsm0808_enc_aoip_trasp_addr(struct msgb *msg, const struct sockaddr_storage *ss) { /* See also 3GPP TS 48.008 3.2.2.102 AoIP Transport Layer Address */ struct sockaddr_in *sin; struct sockaddr_in6 *sin6; uint16_t port = 0; uint8_t *ptr; uint8_t *old_tail; uint8_t *tlv_len; OSMO_ASSERT(msg); OSMO_ASSERT(ss); OSMO_ASSERT(ss->ss_family == AF_INET || ss->ss_family == AF_INET6); msgb_put_u8(msg, GSM0808_IE_AOIP_TRASP_ADDR); tlv_len = msgb_put(msg,1); old_tail = msg->tail; switch (ss->ss_family) { case AF_INET: sin = (struct sockaddr_in *)ss; port = osmo_ntohs(sin->sin_port); ptr = msgb_put(msg, IP_V4_ADDR_LEN); memcpy(ptr, &sin->sin_addr.s_addr, IP_V4_ADDR_LEN); break; case AF_INET6: sin6 = (struct sockaddr_in6 *)ss; port = osmo_ntohs(sin6->sin6_port); ptr = msgb_put(msg, IP_V6_ADDR_LEN); memcpy(ptr, sin6->sin6_addr.s6_addr, IP_V6_ADDR_LEN); break; } msgb_put_u16(msg, port); *tlv_len = (uint8_t) (msg->tail - old_tail); return *tlv_len + 2; } /*! Decode TS 08.08 AoIP transport address IE * \param[out] ss Caller-provided memory where decoded socket addr is stored * \param[in] elem pointer to IE value * \param[in] len length of \a elem in bytes * \returns number of bytes parsed */ int gsm0808_dec_aoip_trasp_addr(struct sockaddr_storage *ss, const uint8_t *elem, uint8_t len) { /* See also 3GPP TS 48.008 3.2.2.102 AoIP Transport Layer Address */ struct sockaddr_in sin; struct sockaddr_in6 sin6; const uint8_t *old_elem = elem; OSMO_ASSERT(ss); if (!elem) return -EINVAL; if (len == 0) return -EINVAL; memset(ss, 0, sizeof(*ss)); switch (len) { case IP_V4_ADDR_LEN + IP_PORT_LEN: memset(&sin, 0, sizeof(sin)); sin.sin_family = AF_INET; memcpy(&sin.sin_addr.s_addr, elem, IP_V4_ADDR_LEN); elem += IP_V4_ADDR_LEN; sin.sin_port = osmo_load16le(elem); elem += IP_PORT_LEN; memcpy(ss, &sin, sizeof(sin)); break; case IP_V6_ADDR_LEN + IP_PORT_LEN: memset(&sin6, 0, sizeof(sin6)); sin6.sin6_family = AF_INET6; memcpy(sin6.sin6_addr.s6_addr, elem, IP_V6_ADDR_LEN); elem += IP_V6_ADDR_LEN; sin6.sin6_port = osmo_load16le(elem); elem += IP_PORT_LEN; memcpy(ss, &sin6, sizeof(sin6)); break; default: /* Malformed element! */ return -EINVAL; break; } return (int)(elem - old_elem); } #endif /* HAVE_SYS_SOCKET_H */ /* Helper function for gsm0808_enc_speech_codec() * and gsm0808_enc_speech_codec_list() */ static uint8_t enc_speech_codec(struct msgb *msg, const struct gsm0808_speech_codec *sc) { /* See also 3GPP TS 48.008 3.2.2.103 Speech Codec List */ uint8_t header = 0; uint8_t *old_tail; bool type_extended; /* Note: Extended codec types are codec types that require 8 instead * of 4 bit to fully specify the selected codec. In the following, * we check if we work with an extended type or not. We also check * if the codec type is valid at all. */ switch(sc->type) { case GSM0808_SCT_FR1: case GSM0808_SCT_FR2: case GSM0808_SCT_FR3: case GSM0808_SCT_FR4: case GSM0808_SCT_FR5: case GSM0808_SCT_HR1: case GSM0808_SCT_HR3: case GSM0808_SCT_HR4: case GSM0808_SCT_HR6: type_extended = false; break; case GSM0808_SCT_CSD: type_extended = true; break; default: /* Invalid codec type specified */ OSMO_ASSERT(false); break; } old_tail = msg->tail; if (sc->fi) header |= (1 << 7); if (sc->pi) header |= (1 << 6); if (sc->pt) header |= (1 << 5); if (sc->tf) header |= (1 << 4); if (type_extended) { header |= 0x0f; msgb_put_u8(msg, header); msgb_put_u8(msg, sc->type); } else { OSMO_ASSERT(sc->type < 0x0f); header |= sc->type; msgb_put_u8(msg, header); } /* Note: Whether a configuration is present or not depends on the * selected codec type. If present, it can either consist of one * or two octets, depending on the codec type */ switch (sc->type) { case GSM0808_SCT_FR3: case GSM0808_SCT_HR3: case GSM0808_SCT_HR6: msgb_put_u16(msg, sc->cfg); break; case GSM0808_SCT_FR4: case GSM0808_SCT_FR5: case GSM0808_SCT_HR4: case GSM0808_SCT_CSD: OSMO_ASSERT((sc->cfg & 0xff00) == 0) msgb_put_u8(msg, (uint8_t) sc->cfg & 0xff); break; default: OSMO_ASSERT(sc->cfg == 0); break; } return (uint8_t) (msg->tail - old_tail); } /*! Encode TS 08.08 Speech Codec IE * \param[out] msg Message Buffer to which IE will be appended * \param[in] sc Speech Codec to be encoded into IE * \returns number of bytes appended to \a msg */ uint8_t gsm0808_enc_speech_codec(struct msgb *msg, const struct gsm0808_speech_codec *sc) { /*! See also 3GPP TS 48.008 3.2.2.103 Speech Codec List */ uint8_t *old_tail; uint8_t *tlv_len; OSMO_ASSERT(msg); OSMO_ASSERT(sc); msgb_put_u8(msg, GSM0808_IE_SPEECH_CODEC); tlv_len = msgb_put(msg, 1); old_tail = msg->tail; enc_speech_codec(msg, sc); *tlv_len = (uint8_t) (msg->tail - old_tail); return *tlv_len + 2; } /*! Decode TS 08.08 Speech Codec IE * \param[out] sc Caller-allocated memory for Speech Codec * \param[in] elem IE value to be decoded * \param[in] len Length of \a elem in bytes * \returns number of bytes parsed; negative on error */ int gsm0808_dec_speech_codec(struct gsm0808_speech_codec *sc, const uint8_t *elem, uint8_t len) { /* See also 3GPP TS 48.008 3.2.2.103 Speech Codec List */ uint8_t header; const uint8_t *old_elem = elem; OSMO_ASSERT(sc); if (!elem) return -EINVAL; if (len == 0) return -EINVAL; memset(sc, 0, sizeof(*sc)); header = *elem; /* An extended codec type needs at least two fields, * bail if the input data length is not sufficient. */ if ((header & 0x0F) == 0x0F && len < 2) return -EINVAL; elem++; len--; if (header & (1 << 7)) sc->fi = true; if (header & (1 << 6)) sc->pi = true; if (header & (1 << 5)) sc->pt = true; if (header & (1 << 4)) sc->tf = true; if ((header & 0x0F) != 0x0F) { sc->type = (header & 0x0F); } else { sc->type = *elem; elem++; len--; } /* Note: Whether a configuration is present or not depends on the * selected codec type. If present, it can either consist of one or * two octets depending on the codec type */ switch (sc->type) { case GSM0808_SCT_FR1: case GSM0808_SCT_FR2: case GSM0808_SCT_HR1: break; case GSM0808_SCT_HR4: case GSM0808_SCT_CSD: case GSM0808_SCT_FR4: case GSM0808_SCT_FR5: if (len < 1) return -EINVAL; sc->cfg = *elem; elem++; break; case GSM0808_SCT_FR3: case GSM0808_SCT_HR3: case GSM0808_SCT_HR6: if (len < 2) return -EINVAL; sc->cfg = osmo_load16be(elem); elem += 2; break; default: /* Invalid codec type => malformed speech codec element! */ return -EINVAL; break; } return (int)(elem - old_elem); } /*! Encode TS 08.08 Speech Codec list * \param[out] msg Message Buffer to which IE is to be appended * \param[in] scl Speech Codec List to be encoded into IE * \returns number of bytes added to \a msg */ uint8_t gsm0808_enc_speech_codec_list(struct msgb *msg, const struct gsm0808_speech_codec_list *scl) { /*! See also 3GPP TS 48.008 3.2.2.103 Speech Codec List */ uint8_t *old_tail; uint8_t *tlv_len; unsigned int i; uint8_t rc; unsigned int bytes_used = 0; OSMO_ASSERT(msg); OSMO_ASSERT(scl); /* Empty list */ OSMO_ASSERT(scl->len >= 1); msgb_put_u8(msg, GSM0808_IE_SPEECH_CODEC_LIST); tlv_len = msgb_put(msg, 1); old_tail = msg->tail; for (i = 0; i < scl->len; i++) { rc = enc_speech_codec(msg, &scl->codec[i]); OSMO_ASSERT(rc >= 1); bytes_used += rc; OSMO_ASSERT(bytes_used <= 255); } *tlv_len = (uint8_t) (msg->tail - old_tail); return *tlv_len + 2; } /*! Decode TS 08.08 Speech Codec list IE * \param[out] scl Caller-provided memory to store codec list * \param[in] elem IE value to be decoded * \param[in] len Length of \a elem in bytes * \returns number of bytes parsed; negative on error */ int gsm0808_dec_speech_codec_list(struct gsm0808_speech_codec_list *scl, const uint8_t *elem, uint8_t len) { /*! See also 3GPP TS 48.008 3.2.2.103 Speech Codec List */ const uint8_t *old_elem = elem; unsigned int i; int rc; uint8_t decoded = 0; OSMO_ASSERT(scl); if (!elem) return -EINVAL; if (len == 0) return -EINVAL; memset(scl, 0, sizeof(*scl)); for (i = 0; i < ARRAY_SIZE(scl->codec); i++) { if (len <= 0) break; rc = gsm0808_dec_speech_codec(&scl->codec[i], elem, len); if (rc < 1) return -EINVAL; elem+=rc; len -= rc; decoded++; } scl->len = decoded; /* Empty list */ if (decoded < 1) { return -EINVAL; } return (int)(elem - old_elem); } /*! Encode TS 08.08 Channel Type IE * \param[out] msg Message Buffer to which IE is to be appended * \param[in] ct Channel Type to be encoded * \returns number of bytes added to \a msg */ uint8_t gsm0808_enc_channel_type(struct msgb *msg, const struct gsm0808_channel_type *ct) { /*! See also 3GPP TS 48.008 3.2.2.11 Channel Type */ unsigned int i; uint8_t byte; uint8_t *old_tail; uint8_t *tlv_len; OSMO_ASSERT(msg); OSMO_ASSERT(ct); OSMO_ASSERT(ct->perm_spch_len <= CHANNEL_TYPE_ELEMENT_MAXLEN - 2); /* FIXME: Implement encoding support for Data * and Speech + CTM Text Telephony */ if ((ct->ch_indctr & 0x0f) != GSM0808_CHAN_SPEECH && (ct->ch_indctr & 0x0f) != GSM0808_CHAN_SIGN) OSMO_ASSERT(false); msgb_put_u8(msg, GSM0808_IE_CHANNEL_TYPE); tlv_len = msgb_put(msg, 1); old_tail = msg->tail; msgb_put_u8(msg, ct->ch_indctr & 0x0f); msgb_put_u8(msg, ct->ch_rate_type); for (i = 0; i < ct->perm_spch_len; i++) { byte = ct->perm_spch[i]; if (i < ct->perm_spch_len - 1) byte |= 0x80; msgb_put_u8(msg, byte); } *tlv_len = (uint8_t) (msg->tail - old_tail); return *tlv_len + 2; } /*! Decode TS 08.08 Channel Type IE * \param[out] ct Caller-provided memory to store channel type * \param[in] elem IE Value to be decoded * \param[in] len Length of \a elem in bytes * \returns number of bytes parsed; negative on error */ int gsm0808_dec_channel_type(struct gsm0808_channel_type *ct, const uint8_t *elem, uint8_t len) { /*! See also 3GPP TS 48.008 3.2.2.11 Channel Type */ unsigned int i; uint8_t byte; const uint8_t *old_elem = elem; OSMO_ASSERT(ct); if (!elem) return -EINVAL; if (len < 3 || len > 11) return -EINVAL; memset(ct, 0, sizeof(*ct)); ct->ch_indctr = (*elem) & 0x0f; elem++; ct->ch_rate_type = (*elem) & 0x0f; elem++; for (i = 0; i < ARRAY_SIZE(ct->perm_spch); i++) { byte = *elem; elem++; ct->perm_spch[i] = byte & 0x7f; if ((byte & 0x80) == 0x00) break; } ct->perm_spch_len = i + 1; return (int)(elem - old_elem); } /*! Encode TS 08.08 Encryption Information IE * \param[out] msg Message Buffer to which IE is to be appended * \param[in] ei Encryption Information to be encoded * \returns number of bytes appended to \a msg */ uint8_t gsm0808_enc_encrypt_info(struct msgb *msg, const struct gsm0808_encrypt_info *ei) { unsigned int i; uint8_t perm_algo = 0; uint8_t *ptr; uint8_t *old_tail; uint8_t *tlv_len; OSMO_ASSERT(msg); OSMO_ASSERT(ei); OSMO_ASSERT(ei->key_len <= ARRAY_SIZE(ei->key)); OSMO_ASSERT(ei->perm_algo_len <= ENCRY_INFO_PERM_ALGO_MAXLEN); msgb_put_u8(msg, GSM0808_IE_ENCRYPTION_INFORMATION); tlv_len = msgb_put(msg, 1); old_tail = msg->tail; for (i = 0; i < ei->perm_algo_len; i++) { /* Note: gsm_08_08.h defines the permitted algorithms * as an enum which ranges from 0x01 to 0x08 */ OSMO_ASSERT(ei->perm_algo[i] != 0); OSMO_ASSERT(ei->perm_algo[i] <= ENCRY_INFO_PERM_ALGO_MAXLEN); perm_algo |= (1 << (ei->perm_algo[i] - 1)); } msgb_put_u8(msg, perm_algo); ptr = msgb_put(msg, ei->key_len); memcpy(ptr, ei->key, ei->key_len); *tlv_len = (uint8_t) (msg->tail - old_tail); return *tlv_len + 2; } /*! Decode TS 08.08 Encryption Information IE * \param[out] ei Caller-provided memory to store encryption information * \param[in] elem IE value to be decoded * \param[in] len Length of \a elem in bytes * \returns number of bytes parsed; negative on error */ int gsm0808_dec_encrypt_info(struct gsm0808_encrypt_info *ei, const uint8_t *elem, uint8_t len) { uint8_t perm_algo; unsigned int i; unsigned int perm_algo_len = 0; const uint8_t *old_elem = elem; OSMO_ASSERT(ei); if (!elem) return -EINVAL; if (len == 0) return -EINVAL; memset(ei, 0, sizeof(*ei)); perm_algo = *elem; elem++; for (i = 0; i < ENCRY_INFO_PERM_ALGO_MAXLEN; i++) { if (perm_algo & (1 << i)) { ei->perm_algo[perm_algo_len] = i + 1; perm_algo_len++; } } ei->perm_algo_len = perm_algo_len; ei->key_len = len - 1; memcpy(ei->key, elem, ei->key_len); elem+=ei->key_len; return (int)(elem - old_elem); } /*! Encode TS 08.08 Cell Identifier List IE * \param[out] msg Message Buffer to which IE is to be appended * \param[in] cil Cell ID List to be encoded * \returns number of bytes appended to \a msg */ uint8_t gsm0808_enc_cell_id_list(struct msgb *msg, const struct gsm0808_cell_id_list *cil) { uint8_t *old_tail; uint8_t *tlv_len; unsigned int i; OSMO_ASSERT(msg); OSMO_ASSERT(cil); msgb_put_u8(msg, GSM0808_IE_CELL_IDENTIFIER_LIST); tlv_len = msgb_put(msg, 1); old_tail = msg->tail; msgb_put_u8(msg, cil->id_discr & 0x0f); switch (cil->id_discr) { case CELL_IDENT_LAC: OSMO_ASSERT(cil->id_list_len <= CELL_ID_LIST_LAC_MAXLEN) for (i=0;iid_list_len;i++) { msgb_put_u16(msg, cil->id_list_lac[i]); } break; case CELL_IDENT_BSS: /* Does not have any list items */ break; default: /* FIXME: Implement support for all identifier list elements */ OSMO_ASSERT(false); } *tlv_len = (uint8_t) (msg->tail - old_tail); return *tlv_len + 2; } /*! Decode Cell Identifier List IE * \param[out] cil Caller-provided memory to store Cell ID list * \param[in] elem IE value to be decoded * \param[in] len Length of \a elem in bytes * \returns number of bytes parsed; negative on error */ int gsm0808_dec_cell_id_list(struct gsm0808_cell_id_list *cil, const uint8_t *elem, uint8_t len) { uint8_t id_discr; const uint8_t *old_elem = elem; unsigned int item_count = 0; OSMO_ASSERT(cil); if (!elem) return -EINVAL; if (len == 0) return -EINVAL; memset(cil, 0, sizeof(*cil)); id_discr = *elem & 0x0f; elem++; len--; cil->id_discr = id_discr; switch (id_discr) { case CELL_IDENT_LAC: while (len >= 2) { cil->id_list_lac[item_count] = osmo_load16be(elem); elem += 2; item_count++; len -= 2; } case CELL_IDENT_BSS: /* Does not have any list items */ break; default: /* FIXME: Implement support for all identifier list elements */ return -EINVAL; } cil->id_list_len = item_count; return (int)(elem - old_elem); } /*! Convert the representation of the permitted speech codec identifier * that is used in struct gsm0808_channel_type to the speech codec * representation we use in struct gsm0808_speech_codec. * \param[in] perm_spch to be converted (see also gsm0808_permitted_speech) * \returns GSM speech codec type; negative on error */ int gsm0808_chan_type_to_speech_codec(uint8_t perm_spch) { /*! The speech codec type, which is used in the channel type field to * signal the permitted speech versions (codecs) has a different * encoding than the type field in the speech codec type element * (See also 3GPP TS 48.008, 3.2.2.11 and 3.2.2.103) */ switch (perm_spch) { case GSM0808_PERM_FR1: return GSM0808_SCT_FR1; case GSM0808_PERM_FR2: return GSM0808_SCT_FR2; case GSM0808_PERM_FR3: return GSM0808_SCT_FR3; case GSM0808_PERM_FR4: return GSM0808_SCT_FR4; case GSM0808_PERM_FR5: return GSM0808_SCT_FR5; case GSM0808_PERM_HR1: return GSM0808_SCT_HR1; case GSM0808_PERM_HR3: return GSM0808_SCT_HR3; case GSM0808_PERM_HR4: return GSM0808_SCT_HR4; case GSM0808_PERM_HR6: return GSM0808_SCT_HR6; } /* Invalid input */ return -EINVAL; } /*! Extrapolate a speech codec field from a given permitted speech * parameter (channel type). * \param[out] sc Caller provided memory to store the resulting speech codec * \param[in] perm_spch value that is used to derive the speech codec info * (see also: enum gsm0808_speech_codec_type in gsm0808_utils.h) * \returns zero when successful; negative on error */ int gsm0808_speech_codec_from_chan_type(struct gsm0808_speech_codec *sc, uint8_t perm_spch) { int rc; memset(sc, 0, sizeof(*sc)); /* Determine codec type */ rc = gsm0808_chan_type_to_speech_codec(perm_spch); if (rc < 0) return -EINVAL; sc->type = (uint8_t) rc; /* Depending on the speech codec type, pick a default codec * configuration that exactly matches the configuration on the * air interface. */ switch (sc->type) { case GSM0808_SCT_FR3: sc->cfg = GSM0808_SC_CFG_DEFAULT_FR_AMR; break; case GSM0808_SCT_FR4: sc->cfg = GSM0808_SC_CFG_DEFAULT_OFR_AMR_WB; break; case GSM0808_SCT_FR5: sc->cfg = GSM0808_SC_CFG_DEFAULT_FR_AMR_WB; break; case GSM0808_SCT_HR3: sc->cfg = GSM0808_SC_CFG_DEFAULT_HR_AMR; break; case GSM0808_SCT_HR4: sc->cfg = GSM0808_SC_CFG_DEFAULT_OHR_AMR_WB; break; case GSM0808_SCT_HR6: sc->cfg = GSM0808_SC_CFG_DEFAULT_OHR_AMR; break; default: /* Note: Not all codec types specify a default setting, * in this case, we just set the field to zero. */ sc->cfg = 0; } /* Tag all codecs as "Full IP" * (see als 3GPP TS 48.008 3.2.2.103) */ sc->fi = true; return 0; } /*! @} */